title: Novel techniques of preparing TEM samples for characterization of irradiation damage.
abstract: Focus ion beam preparation of transmission electron microscopy (TEM) samples has become increasingly popular due to the relative ease of extraction of TEM foils from specific locations within a larger sample. However the sputtering damage induced by Ga ion bombardment in focus ion beam means that traditional electropolishing may be a preferable method. First, we describe a special electropolishing method for the preparation of irregular TEM samples from ex-service nuclear reactor components, spring-shaped spacers. This method has also been used to prepare samples from a nonirradiated component for a TEM in situ heavy ion irradiation study. Because the specimen size is small (0.7 × 0.7 × 3 mm), a sandwich installation is adopted to obtain high quality polishing. Second, we describe some modifications to a conventional TEM cross-section sample preparation method that employs Ni electroplating. There are limitations to this method when preparing cross-section samples from either (1) metals which are difficult to activate for electroplating, or (2) a heavy ion irradiated foil with a very shallow damage layer close to the surface, which may be affected by the electroplating process. As a consequence, a novel technique for preparing cross-section samples was developed and is described.
authors.affiliation: Department of Mechanical and Materials Engineering, Queen's University, Kingston, Ontario, Canada, K7L 3N6.
authors.forename: H K
authors.initials: HK
authors.lastname: Zhang
authors.forename: F
authors.initials: F
authors.lastname: Long
authors.forename: Z
authors.initials: Z
authors.lastname: Yao
authors.forename: M R
authors.initials: MR
authors.lastname: Daymond
keywords: Cross-section; Inconel X-750; TEM sample preparation; small samples; twin jet electropolishing